Under Miller’s leadership from 1966-1982, the MLBPA achieved the right to free agency—a victory that greatly affected baseball and all pro sports going forward. In 1968, Miller negotiated the first collective bargaining agreement in professional sports.

Fittingly, the tributes to Miller have poured in from across the sports world. And today’s players expressed their gratitude for the many battles Miller won for them decades ago.

Some of the reaction from league executives:

“It is with profound sorrow that we announce the passing of Marvin Miller. All players—past, present and future—owe a debt of gratitude to Marvin, and his influence transcends baseball. Marvin, without question, is largely responsible for ushering in the modern era of sports, which has resulted in tremendous benefits to players, owners and fans of all sports.

“It was an honor and a privilege to have known Marvin. The industry has never witnessed a more honorable man, and his passion for helping others and his principled resolve serve as the foundation of the MLBPA to this day. On behalf of all Major Leaguers and MLBPA staff, I extend my heartfelt sympathies to Marvin’s daughter, Susan, son, Peter, their families and Marvin’s many friends and admirers. Marvin was a champion among champions, and his legacy will live on forever.”

— MLBPA executive director Michael Weiner

“Marvin Miller was a highly accomplished executive and a very influential figure in baseball history. He made a distinct impact on this sport, which is reflected in the state of the game today, and surely the Major League players of the last half-century have greatly benefited from his contributions. On behalf of Major League Baseball and the 30 Clubs, I extend my deepest condolences to Marvin’s family, friends and colleagues.”

— MLB commissioner Bud Selig (via MLB.com)

“Marvin possessed a combination of integrity, intelligence, eloquence, courage and grace that is simply unmatched in my experience. Without question, Marvin had more positive influence on Major League Baseball than any other person in the last half of the 20th century. It was a rare privilege for me to be able to work for him and with him. All of us who knew him will miss him enormously.”

“Marvin exemplified guts, tenacity and an undying love for the players he represented. He was a mentor to me, and we spoke often and at length. His most powerful message was that players would remain unified during labor strife if they remembered the sacrifices made by previous generations to make the game better. His passion for the players never faltered, and men in women across all sports are in a better place thanks to his tireless work.”

— NFLPA executive director DeMaurice Smith

“Marvin was the definition of a leader. By challenging team owners and league commissioners and successfully protecting and enhancing the rights of players, he proved that labor unions were necessary in sports.”

— NFLPA President Domonique Foxworth

And some of the reaction from players:

"RIP Marvin Miller 95, former Exec Director @MLB_PLAYERS One of most influential figures in @MLB history. Should be in @BaseballHall"

— Hall of Fame OF Dave Winfield (@DaveWinfieldHOF)

“Marvin Miller was an incredible man. We are all grateful for his contributions -- his legacy will live on for generations...”

— Detroit Tigers SP Justin Verlander ‏(@JustinVerlander)

“Marvin Miller-legendary leader of MLB players. R.I.P. -Travesty that he's not in Hall of fame!”

— Former major league SP David Cone (‏@YESConeZone36)

“Thank you, Marvin Miller!! #rip”

— Tampa Bay Rays SP David Price (‏@DAVIDprice14)

"Today we remember Marvin Miller, founder of the #MLBPA. We have him to thank for the best #union in sports! R.I.P Marvin."

— Tampa Bay Rays 3B Evan Longoria (@Evan3Longoria)

“Sad to hear about the passing if Marvin Miller. He will be missed. A true pioneer. Thank you Marvin.”

— New York Mets SP R.A. Dickey ‏(@RADickey43)

“RIP to Marvin Miller... a guy who stood up for what was right. Your name will not be forgotten in the MLB Family. Thank you”

— Pittsburgh Pirates CF Andrew McCutchen (‏@TheCUTCH22)

“RIP Marvin Miller...a man who lead baseball to where it is today! Thank u for being a pioneer for us all.”

— Free agent OF Shane Victorino (‏@ShaneVictorino)

“RIP Marvin Miller thank you for all you did for #MLBPA”

— Atlanta Braves SP Paul Maholm ‏(@paul_maholm)

“Sad to hear of the passing of Marvin Miller; It's because of his work years ago we get to enjoy our careers today #MLB #Union”

— Cleveland Indians RP Chris Perez ‏(@ChrisPerez54)

“RIP Marvin Miller. A major game changer for MLB players! My family and I are VERY thankful for the changes you brought about!”

— Kansas City Royals DH Billy Butler (‏@BillyButlerKC)

“RIP Marvin Miller. The 1st Executive Dir of @MLB_PLAYERS,a great man & leader to whom entire baseball family owes a great deal of gratitude.”

— Kansas City Royals SP Jeremy Guthrie (‏@TheRealJGuts)

“RIP Marvin Miller. A class act that pioneered the way for our MLB players. We are all in debt to him. #RIP”

— Houston Astros SP Bud Norris (‏@BudNorris20)

“Thoughts and prayers to the family of Marvin Miller, a leader, pioneer, and renaissance man who changed the course of baseball. Thank you”